For a boiling-water nuclear reactor, what has been developed in recent years is a device in which FPGA (field programmable gate array) is applied to a power range monitor (PRM), which is used to measure a neutron flux inside a nuclear reactor in power outputting operation state, a startup range neutron monitor (SRNM) and the like. The FPGA is a type of integrated logic element that can write a unique logic circuit.
As shown in FIG. 2, an average power range monitor (APRM), a local power range monitor (LPRM) and the like that make up the above-described power range monitor (PRM) make up modules, each of which is made up of a variety of boards. The components as a whole make up a digital processing monitoring device that monitors the output power of a nuclear reactor. The digital processing monitoring device is made up of a plurality of modules (See Japanese Patent Application Laid-Open Publication No. 2007-3399, the entire content of which is incorporated herein by reference.).
In the case of conventional modules, boards have been developed for each module. Therefore, maintenance and inspection are required for each module. Thus, a board used in a given module cannot be applied to another module. Accordingly, for example, when it is found as a result of the maintenance and inspection of a module that it is necessary to replace a board, a board for the above-described module needs to be used. Therefore, various types of replacement board need to be prepared in accordance with the types of the modules. Thus, maintenance and inspection are complex and expensive.
Therefore, the object of the present invention is to provide a digital processing monitoring device with improved economic efficiency and maintainability in which the number of types of board required is reduced thanks to versatile boards.